Isham



2 Sheets-Sheet F ISHAM -& MARCY. Manufacture of Steel from Iron.-

Patented 0m. 2, 1849.

Ens. Photo-Lilhographur. Wnhinflun. D. c.

2 Sheets-Sheet 2;

Patented Oct. 2,' 3849.-

'ISHAM & MARCY. Manufactufe of Steel from Iron.

Q0 & W e e N m e UNiTnn STATES N. M. ISHAM AND E. E. MAROY, OF HARTFORD,CONIVEOTIOUT.

PROCESS FOR MAKING STEEL.

Specification forming part of Letters Patent No. 6,760, dated October 2,1849; antedatcd November 2, 1848.

To all whom it may concern Be it known that we,'NoRirAN M. ISHAM andERASTUS E. DIARCY, joint inventors, of the city of Hartford and State ofConnecticut, have invented a new and useful Improvement in the Art ofConverting Iron Ores and Cast- Iron, Unmixed with any Malleable Iron,into Steel; and we do hereby declare that the nature of our inventionand the method of operation are fully set forth in the followingspecification and accompanying drawings, making a part of thisspecification.

To enable others to make and use our said invention, we proceed todescribe the apparatus, its construction, and mode of operation.

The first process in our manufacture of steel is to fuse eithercast-iron or iron ore judiciously selected in a cupola furnace chargedafter the ordinary method, but urged by blasts of hot carbonieoxide gas.This is accomplished by attaching to a common cupola-furnace (charged inall respects after the ordinary method of melting pig-iron) tworeceptacles or reservoirs, A and B, Figure 3, similar to thoserepresented by O in Fig. l and by O and D in Fig. 2, and of sufficientsize to hold a quantity of charcoal, which shall not be all consumeduntil the iron is melted. The receptacles which are to be attached tothe cupola-furnace in the manner as shown by Fig. 8 are to be chargedwith charcoal andignited by the time the fuel in the cupola-furnace isready for the blast. Now, instead of applying the air-blasts directly tothe cupola-furnace, they are to be applied to the receptacles, as at aa, Fig. 3. and the iron is melted by the aid of the hot carbonic-oxidegas thus produced, and cast in chills. By this preparatory process themetal acquires some of the properties of steel, and becomes so modifiedin its character as to be more readily convertible into good steel bythe process hereinafter described.

The process of refining steel is as follows: The metal, having beenfirst prepared in the manner and by the apparatus above described, isplaced in the bed of the furnace A, Fig. 1, and covered with charcoal.The receptacles or reservoirs C, Fig. 1, and C D, Fig. 2, are thenfilled with charcoal, ,and when thoroughly ignited the lids are put onand luted down to prevent an escape of gas. An airblast, which must beregulated by the judgment of the operator, is then to be applied at theapertures D and E, Figs. 1 and 2. This blast by passing through thereceptacles creates a gaseous oxide of carbon-,- whieh is driven uponthe iron in the furnace through the tuyere f. In addition to thiscurrent of gaseous carbon there must be another air-blast passing intothe furnace through branch m of the pipe 2', regulated by the damper 0,so as to admit atmospheric air sufficient to produce the combustionrequired to melt the metal. NVhen melted,the metal is to be worked afterthe ordinary process adopted in refining iron. An important part of theprocess consists in graduating by means of the valves 0 0 0 0 0 the proportions of gaseous carbon and of atmospheric air thrown into thefurnace, so as to bring the metal to nature, and at the same time toconvert it into steel. Nodefinite rules can be given to determine theexact proportions of gaseous carbon and atmospheric air requisite toproduce this conversion, for much depends on the quality and quantity ofthe metal to be converted, and on the judgment and skill of the operatorin conducting the process, which should be continued until the metal isproperly brought to naturethat is, sufficiently refined to ballwhen itshould be taken out and carefully forged into blooms. Skill is requiredto enable the operator to treat the metal in the furnace, and todetermine that precise degree of refinement and carbonization which isrequisite to produce the best steel. This can be obtained by practicaleX- perience only.

Fig. 1 of the annexed drawings represents a transverse vertical sectionof the apparatus, and Fig. 2 a-transverse horizontal section of thesame.

In Fig. 1, A is the furnace; a, the front opening for same; B, the stackor chimney; I), the flue in same; 0, the valve or damper for regulatingdraft of flue; d, an iron door for. closing front of furnace, regulatedby weight and chain passing over pulley e,- ff, notches in front plateof furnace to support the bars when working the metal; 9 g9, holes infront plate for dipping out the cinder; h, tnyere surrounded by waterconveyed through pipes i i, and entering the furnace near the 0d, andthe apparatus used therein.

bottom; 0, receptacle or reservoir, cylinder shape, made of iron, andlined with firebrick; j, grate in bottom of same; K, ashpit; D,blast-pipe entering ash-pit of receptacle O at Z,- E, branch ofblast-pipe passing from near top of receptable G into furnace A throughtuyere h,- m m, valves in the blastpipe.

In Fig. 2, A represents interior of furnace, a bottom plate, and b bb 1) side plates of castiron inclosing the fire, on which the metal isworked; 0, door of iron for closing front of furnace; d, cast-ironhearth; e e, cast-iron plates inclosing the furnace; f, tuyere; B, stackor chimney; g, flue; h, valve or damper in fine for regulating draft; *6i 1', bolts for securing chimney in place; 0, charcoal-receptacle,closed; j, door for charging sanie, which may be either in the top, asin the drawings, or in the sides; D, another receptacle, with coverremoved, showing grate k k at bottom; E, blastpipe; 1 l, branchesentering receptacle at bottom; m, branch of same entering tuyere at f,"

n 12, branches of same passing from near top of receptacle 0 and D andjoining branch m at tuyeref; 0 0 0 0 0, valves or dampers for regulatingblasts. To reduce the blooms into bars they should be heated in asuitable heating-furnace and subjected to the tilt-han1mer. During theworking of the metal in the furnace A, Fig. 1, it should be carefullycovered with charcoal, and the external air excluded as much as possibleby means of the door D,'

Fig. 1.

The above is a general description of the process necessary to producesteel by our meth- There are, however, some particulars relating to theworking of our plans of the highest consequence and absolutely necessaryto perfect success. The great importance of the first process is theeffect thus produced on the metal,

which seems to be a chemical union of a sufficient quantity of carbonequally throughout the whole mass of iron, by which it attains theproperties of impure steel, and particularly fit it for the secondprocess, for which it was never before discovered to be adapted, andwithout obtaining metal in the state in which the first process leavesit we find it impossible to make a perfect steel without the use ofmalleable iron, which has always heretofore been used in whole or inpart in the conversion of iron into steel. In the second process we areobliged to confine ourselves within very narrow limits as to proportion,position, and direction of the blast, or the result will be entirelymarred or spoiled, as has been proved by numerous experiments.

ter the furnace in a horizontal position. It

The tuyere must en-- should be about five and threefourths inches incircumference at the orifice and seven inches and three-fourths abovethe bottom plate, where the latter is eighteen by twenty inches, formaking loops of eighty or one hundred pounds. In larger furnaces thetuyere should be a little higher.

We find that the apparatus heretofore used for refining steel by any ofthe known modes is wholly insufficient for our purposes. This we desireto call particular attention to, as it is very important to secure ourparticular apparatus, as clearly illustrated in the drawings. Thepeculiarities of our process may therefore be thus concisely summed up:First, we use no malleable iron, but melt the pig-iron or ore by the aidof the hot carbonic-oxide blast thown directly upon the iron in the cupo1a-furnace through a tuyere entering the furnace at or near the bottom.This very essentially modifies the character of the metal, as beforestated, by which it is prepared to be submitted to the second process,in which it is placed in a refining-furnace, covered with charcoal, andsubjected to a horizontal blast of hot carbonicoxide gas and atmosphericair, commingled and in requisite proportions, properly regulated byvalves, as described, till the metal is worked into a ball of malleablesteel, ready to be forged into bars.

WVe take occasion here to observe that since our invention the hotcarbonic-oxide blast has been applied to some extent in the manufactureof iron both in Europe and America; but we have priority and originalityin the mode of application, as herein described, of this im- I portantgas to the manufacture of steel.

\Ve do not claim to have been the first who have melted iron in a commoncupola-furnace charged in the usual manner and urged by blasts of hotcarbonic-oxide gas; but

WVhat we do claim as our invention, and dcsire to secure by LettersPatent, is

1. The process herein described of manufacturing steel by producing,first, a metal imperfectly converted in the cupola-furnace, in themanner described, and then submitting said metal to the refinery,constructed as herein described, where the article is perfected by themeans above made known.

2. The horizontal blast in the refining-furnace, as above moreparticularly stated, for blowing a blast of carbonic oxide, as hereinset forth.

NORMAN M. ISHAM.

ERASTUS E. MARGY.

Vitnesses:

Biol-mun D. HUBBARD, Honarro XV. SHIPMAN.

